Thiolate-Bridged Nickel–Iron and Nickel–Ruthenium Complexes Relevant to the CO-Inhibited State of [NiFe]-Hydrogenase
datasetposted on 22.02.2016, 00:00 by Puhua Sun, Dawei Yang, Ying Li, Yahui Zhang, Linan Su, Baomin Wang, Jingping Qu
By employing S(CH2CH2S–)2 (tpdt) and O(CH2CH2S–)2 (opdt) as bridging ligands, two nickel–iron and two nickel–ruthenium heterodimetallic complexes, [Cp*M(μ-1κ3SSS′:2κ2SS-tpdt)Ni(dppe)][PF6] (1, M = Fe; 3, M = Ru) and [Cp*M(μ-1κ3SSO:2κ2SS-opdt)Ni(dppe)][PF6] (2, M = Fe; 4, M = Ru) (Cp* = η5-C5Me5; dppe = Ph2P(CH2)2PPh2), were obtained by a one-pot synthetic method and were identified by spectroscopy and X-ray crystallography. At 1 atm of CO, the pendant oxygen atom dissociated from the iron or ruthenium center and rapidly transferred to the nickel center when a CO molecule attacked the iron or ruthenium center in 2 and 4. However, there was no similar reaction occurring in 1 and 3 with the pendant sulfur atom. We confirmed the solid-state structure of the CO complex [Cp*Fe(t-CO)(μ-1κ2SS:2κ3SSO-opdt)Ni(dppe)][PF6] (5), which represents a possible configuration in the CO-inhibited state of [NiFe]-hydrogenase and exhibits no catalytic activity in electrochemical proton reduction.